Multi-ply sheet former



June 28, 1960 E. D. BEACHLER 2,942,661

MULTI-PLY SHEET FORMER Filed Dec. 18, 1956 [17 V5 27 [U r 50 w/mo 0. 55/20/459 MULTI-PLY SHEET FORIVIER Edward D. Beachler, Beloit, Wis., assignor to Beloit Iron Works, Beloit, Win, a corporation of Wisconsin Filed Dec. 18, 1956, Ser. No. 629,070

2 Claims. (31. 162-304) This invention relates to paper making machines and more particularly to an improved apparatus for forming multi-ply sheets of paper, paperboard and the like.

In the conventional endless band or Fourdrinier type paper making machine, water is removed from stock on the upper run of the band or wire by passing the wire over a series of stationary suction boxes. The degree of evacuation of these suction boxes must be varied so that greater suction is available in the box closest to the conventional couch roll. As a result, greater wear is effected on the wire at this point and the life span of the wire is greatly diminished.' Because of the limited dewatering potential of such an arrangement it was difficult to form multi-ply sheets on a Fourdrim'er type of machine. Furthermore, where multi-ply sheets having plies of varying characteristics, such as color, were formed in machines of this type, the effluent water from the several pulp layers was necessarily intermixed with the result that pulp from the different kinds of stock could not be effectively recovered for reuse.

A primary object of the invention is, therefore, to provide apparatus for forming multi-ply sheets of paper, paperboard and the like wherein a plurality of layers of pulp may be deposited in superimposed relation on a Fourdrinier Wire and in which water may be removed from the several pulp layers as deposited so that the water may be segregated for separate recovery of pulp therefrom.

Another object of the invention is to provide paper making apparatus of the Fourdrinier type in which wear on the Fourdrim'er wire is substantially reduced by the provision of rotatable foraminous cylinders for dewatering the stock, each of the cylinders being connected to a vacuum source.

A further object of the invention is to provide apparatus for forming a multi-ply sheet of paper, paperbomd and the like in which a plurality of foraminous cylinders are rotatably mounted in spaced relation in engagement with the inner surface of an endless Fourdrinier wire, in which each of the cylinders is connected to a vacuum source, and in which successive layers of pulp are deposited on the wire at the several cylinders so that the effluent water from the several layers may be effectively segregated.

A further object of the invention is to provide apparame for forming a multi-ply sheet of paper, paperboard and the like in which a plurality of stock inlets are arranged in series along the length of an endless Fourdrinier wire for the depositing of successive layers of pulp thereon, and in which a vacuum source is arranged in register with each of the stock inlets so that the layers are formed on the wire in superimposed relation and the efiluent water from the several layers may be separately removed for subsequent recovery.

A more particular object of the inventon is to provide apparatus for forming -a multi-ply sheet of paper, paperboard and the like in which a plurality of foraminous cylinders are rotatab-ly mounted in spaced relation in nited States Patent Patented June 28, 1960 therefrom.

Another object of the invention is to provide apparatus for forming a multi-ply sheet of paper, paperboard and the like in which a plurality of stock inlets are arranged in series along the length of a \Fourdrinier wire so that successive layers of pulp are deposited thereon, and in which a suction type forming unit is arranged in register with each of the stock inlets for removal of water from each pulp layer as it is formed so that the water from the several layers maybe readily segregated for subsequent separate recovery of pulp therefrom.

These and other objects of the invention will be apparent from time to time as the specification proceeds and with reference to the accompanying drawing wherem:

V Figure 1 is an elevational diagrammatic view of the forming end of a Fourdrinier type paper making machine equipped with stock feed and water removal apparatus in accordance with the present invention;

Figure 2 is an enlarged fragmentary elevational view, also diagrammaticin nature, showing in more detail the apparatus of the present invention in operative relation to a Fourdrinier wire of conventional type; and

Figure 3 is a vertical sectional view of a modified form of vacuum source which may be used in lieu of the'arrangement shown in Figures 1 and 2.

As shown on the drawing:

In Figure l the reference numeral .10 designates generally an endless band or Fourdrinier type paper making machine including a looped forming wire 12 trained between a roll 14 and a couch roll 16. Stationary suction boxes 18 may be mounted the loop of the wire 12 in engagement with the undersurface of the upper run of the wire. According to the present invention, a first foraminous roll 20 is rotatably mounted in engagement with the inner surface of the wire v12 in a manner that a continuous wrapped zone 21 is formed about the periphery of the roll 20. The roll '20 is surrounded by an enclosure 22 which may be connected by means of a conduit 24 to a suitable source of vacuum (not shown). The enclosure 22 has an opening 23 through which a portion of the periphery of the cylinder 20 extends and which provides communication between the interior of the enclosure and the wrapped zone 21 of the wire 12. A first stock inlet 26- is arranged for depositing stock on the outer surface of the wire .12 within the confines of the zone 21 and in register with the cylinder 20. As the stock is deposited, water is extracted therefrom by suction within the enclosure 22 and may be carried ed for subsequent recovery of the re maining pulp in a conventional manner.

A second stock inlet 28 is arranged in spaced relation to the first stock inlet 26 for depositing stock on the pulp layer from the first stock inlet. The stock inlet 28 is arranged in register with a second foraminous cylinder 30 which is rotatably mounted in spaced relation to the first foraminous cylinder 20 and also engages the undersurface of the wire 12, thereby forming a continuous wrapped zone 31. The cylinder 30 may be surrounded by an enclosure 32 connected by a conduit 34 to a source of vacuum (not shown). The enclosure 32 has an opening 33 through which a portion of the periphery of the cylinder 30 extends and which provides communication between the interior at the enclosure and the wrapped zone 31 of the wire 12 for forming the second pulp layer and removing water therefrom. "Since the evacuated enclosure 32 must pull water through both of the'pulp layers, the degree of evacuation within the enclosure 32 may be somewhat higher than that of the enclosure 22. The Water thus withdrawn may then be treated for recovery of any pulp remaining. According to the present invention, vja multi-ply sheet having fiber layers of varying characteristics may be formed and the effluent waters from the several layers are immediately separated from the'stock as the pulp layer is formed so that intennixing of water from the several pulp layers 'is prevented. This arrangement is particularly ad vantageous in :the forming of-paper andpaperb oard'in which one ply is of ahigher fiber quality than the otherply, or where the several pliesvary incolor; It; will be appreciated thatthe numberofiformingunits employed maybevaried. at will to obtain afinished product of any desired number of plies. The removal of water from the stock layers as formed'by the cylinders 20 and 30 obviates the need for a long series of suction boxes 18." In

- zone, and conduit means within the. wire loop and connecting with the enclosure and with a vacuum source to apply'a negative pressure .to' the stock slurry during' deposition in the wrappingzone to withdraw efiluent water for subsequent. recovery, each fonning unit being Li independent of another forming unit 'to'the extent that stock slurries of diiferent characteristics can be deposited upon the wire in the spaced wrapping'zo'nes and the eflluent water from each slurry separately removed without admixing to permit re-using the same. a

the present instance, the suction boxesmay be entirely;

, eliminated with a'consequent. decrease in wear of the forming wire 12. Where the boxes 18 are utilized, however, they may. be operated at a higherpressure or a" lower degree of vacuum. so that women the forming wire 12is diminished.

In Figure 3 is shown a modified form of suctionfonning-unit that may be employed instead of theforaminous cylinder and evacuated enclosure arrangement of Figs. 1, 2 and 3. This suction forming unit, indicated generally by;I6f6Z6l1C6 numeral 36, includes a rotating perforated shell' 38,. a' stationary suction gland 40 within the shell 38, and circumferentially spaced seals 42; The

space within the gland 40 may be connected to a suitable source ofvacuum (not shown) for removal of water from V 'a pulplayer through the perforations of the shell 38, as

will be understood. Both the cylinder 20 and the cylinder may be replaced by a suction forming unit of the ,type shown in Figure 3. As in the principal form of the invention, water removed from the several layers as they are formed is immediately segregated for a separaterecovery of pulp therefrom.

It will be understood that various modifications and variations of the present invention may be efiected without departing from the spirit and scope of the novel concepts thereof.

' I claim as my invention:

1. In a paper machine havingan endless forming wire wrapping a plurality of rolls and defining therewith acontinuous Wire loop movable across at least one vacuum box, the improvement which comprises a plurality of spaced forming units each located upstream of the vacuum box to' successively deposit a stock slurry upon the forming wire to provide a multi-ply web and to successively and separately remove efliuent water from the slurry during deposit upon the wire, each forming unit comprising a foraminous rotatable roll within the wire loop and defining.

2. In a paper machine having an endless forming wire wrapping aplurality' of rolls and defining therewith a continuous wire loop movable across at least one'vacuum box, the improvement which comprises a plurality of spaced forming units each'located upstream of the V vacuum box to successively deposit a stock slurry upon the forming wire to provide a multi-ply web and to successively and separately remove eflluent water from the slurry during deposit upon .thewire, each, forming unit comprising a perforated rotatable. shell within the wire loop and wrapped thereby and defining awrapping zone therewith, a stationary suction V gland interiorly of the shell connected tov a sourceof vacuum, seal means spaced along the inner diameter of'the shell and connecting with the suction gland todefine an accurate length along said diametersuhstantially coextensive with the wrapping zone,

and a stock inlet outside the wire loop and shaped to define'a tangential flow path for the stock slurry relative to the direction of travel of the forming wire along the wrapping zone, the stock slurry during deposition in the wrapping zone having a negative pressure applied thereto to withdraw efiiuent water for subsequent recovery, each forming unit being independent of another forming unit to the extent that stock slurries of different characteristics can be deposited upon the wire in the spaced wrapping zones and the eflluent water from each slurry separately removed withontadmixing to permit re-using the same.

References Cited in the file of this patent UNITED STATES PATENTS Simpson July 10,1956 

